AIMS: To assess the feasibility, safety and effectiveness of intravascular brachytherapy (VBT) in routine clinical practice. METHODS AND RESULTS: Between April 1999 and September 2000, 1098 consecutive patients treated in 46 European centres by intraluminal irradiation using a Sr/Y(90)source train (BetaCath, Novoste, GA) were included in a registry, and follow-up data were obtained for 98.8% of them after 6.3+/-2.4 months. Eight hundred and forty (76.5%) patients were males, and mean age was 62.0+/-10.2 years. Two hundred and seventy-one (26.9%) had unstable angina, and 256 (23.5%) were diabetics. Nine hundred and thirteen lesions (77.7%) were the result of in-stent restenosis, 208 (17.7%) were de novo lesions and 48 (4.1%) non-stented restenotic lesions. Mean estimated reference diameter was 3.2+/-0.5mm and mean estimated lesion length was 19.0+/-11.8mm. The prescribed radiation dose was 18.8+/-3.2Gy. Multivessel irradiation was done in 6.2% of cases, and a new stent was implanted in 29.6% of cases. Most patients received 6 or 12 months of combined aspirin and thienopyridin treatment after the procedure. Technical success was obtained in 95.9% of treated lesions, and the in-hospital major adverse cardiac event (MACE) rate was 1.8%. At follow-up, the MACE rate was 18.7% (1.9% deaths from any cause, 2.6% AMI, 13.3% TVR by PCI and 3.3% TVR by CABG). CONCLUSION: The major current application of VBT is the treatment of in-stent restenosis. The good results of VBT observed in recent randomized controlled trials can be reproduced in clinical practice.